As more natural lands are transformed into urban lands with more people in urban areas, it is important to understand how these environmental changes may impact living conditions as well as the ecosystem. This book summarizes current satellite observing capacities and the growing demand for consistent and continuous local, regional, and global observation data by different government agencies in many countries and research groups. It provides academic faculties, students, researchers, and government decision makers an up-to-date reference that summarizes the state of the art in both remote sensing techniques and environmental assessment methods.